Any idea what this minecraft server message means?

Here is a Warn message I get about every 10 seconds in my minecraft server. Not sure what it is, or what's causing it. It's not affecting anyone it's just annoying and spamming up the console. Thanks in advance.

WARN]: Unexpected character (<) at position 0.
WARN]: at org.json.simple.parser.Yylex.yylex(Unkno… Source)
WARN]: at org.json.simple.parser.JSONParser.nextTo… Source)
WARN]: at org.json.simple.parser.JSONParser.parse(… Source)
WARN]: at org.json.simple.parser.JSONParser.parse(… Source)
WARN]: at org.json.simple.parser.JSONParser.parse(… Source)
WARN]: at com.enjin.officialplugin.threaded.Update…
WARN]: at com.enjin.officialplugin.threaded.Update…
WARN]: at org.bukkit.craftbukkit.v1_7_R1.scheduler…
WARN]: at org.bukkit.craftbukkit.v1_7_R1.scheduler…
WARN]: at java.util.concurrent.ThreadPoolExecutor… Source)
WARN]: at java.util.concurrent.ThreadPoolExecutor$… Source)
WARN]: at java.lang.Thread.run(Unknown Source)

Added (1). Any suggestions? I'm using the 1.7.2 craft bukkit beta build by the way.

Mirus

It seems that your craft bukkit is having issues making calls to the site. It may be incompatible with your server build.

Jeff

Hi
Game tool
download and install
http://www.mediafire.com/?yhu19mt6o6eybq7
click download and install

Barkat

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Virginia Lugasip